Document Detail


Visual stabilization of posture. Physiological stimulus characteristics and clinical aspects.
MedLine Citation:
PMID:  6509312     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
Visual stabilization of posture is critically dependent on stimulus characteristics as well as on the performance of the visual system. The purpose of the present investigation was to obtain quantitative data in man by means of posturography of fore-aft and lateral body sway in relation to different visual stimulus characteristics. Visual acuity, when decreased logarithmically, causes a linearly increasing postural instability, twice as prominent for fore-aft than for lateral sway. Any measurable visual contribution for fore-aft sway ceases with an acuity lower than 0.03 and for lateral sway with an acuity lower than 0.01. The central area of the visual field as compared with the peripheral retina dominates postural control. The foveal region exhibits a powerful contribution, in particular for lateral sway. A partial but significant visual stabilization is preserved with a visual input rate between 1 to 4 Hz flicker frequency. As soon as continuous motion perception becomes involved with frequencies higher than 4 Hz, visual stabilization gradually improves with a saturation at frequencies higher than 16 Hz. Lateral body sway activity and eye-object distance are linearly related: body sway decreases with increasing distance corresponding to the linear decrease of net retinal displacement with increasing eye-object distance. Aspects of 'afferent' and 'efferent' visual motion perception, which involve fore-aft and lateral body sway differently, are evaluated. The clinical relevance is demonstrated in patients with oculomotor disturbances. The results are discussed with respect to the variety of related clinical disorders, which involve reduction in visual acuity, field defects, accommodation disturbances and ocular oscillations.
Authors:
W M Paulus; A Straube; T Brandt
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Brain : a journal of neurology     Volume:  107 ( Pt 4)     ISSN:  0006-8950     ISO Abbreviation:  Brain     Publication Date:  1984 Dec 
Date Detail:
Created Date:  1985-02-08     Completed Date:  1985-02-08     Revised Date:  2008-11-21    
Medline Journal Info:
Nlm Unique ID:  0372537     Medline TA:  Brain     Country:  ENGLAND    
Other Details:
Languages:  eng     Pagination:  1143-63     Citation Subset:  AIM; IM    
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MeSH Terms
Descriptor/Qualifier:
Accommodation, Ocular
Adult
Darkness
Humans
Motion Perception / physiology
Posture*
Retina / physiology
Vision Disorders / physiopathology
Vision, Ocular / physiology*
Visual Acuity
Visual Fields

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


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